/*
 * Copyright (c) 2017. Real Time Genomics Limited.
 *
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the
 *    distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package com.rtg.simulation.reads;

import com.rtg.simulation.GaussianSampler;

/**
 * Choose values according to a Gaussian distribution specified by outer bounds plus the number of deviations that
 * should fall within the bounds.
 */
public class MinMaxGaussianSampler extends GaussianSampler {

  private static final int NUMBER_TRIES = 1000;

  private final int mMin;
  private final int mMax;

  /**
   * Constructor, occupying four standard deviations of a Gaussian
   * @param min the minimum value to output
   * @param max the maximum value to output
   */
  public MinMaxGaussianSampler(int min, int max) {
    this(min, max, 4);  // default 2 std devs per side
  }

  /**
   * Constructor
   * @param min the minimum value to output
   * @param max the maximum value to output
   * @param numDevs the number of standard deviations to include
   */
  public MinMaxGaussianSampler(int min, int max, double numDevs) {
    super((max + min) * 0.5 + 0.5, (max - min) / numDevs);
    mMin = min;
    mMax = max;
    if (mMax < mMin) {
      throw new IllegalArgumentException();
    }
  }

  @Override
  public int next() {
    for (int x = 0; x < NUMBER_TRIES; ++x) {
      final int fragLength = super.next();
      if ((fragLength >= mMin) && (fragLength <= mMax)) {
        return fragLength;
      }
    }
    return Integer.MIN_VALUE;
  }
}
